Turbine system utilizing hot driving gases



MalCh 30, 1948. J4. s. HAvERsrlc/:K 2,438,535

TURBINE SYSTEM UTILIZlNG HOT DRIVING GASES Mil-fdl 30, 1948 J. s. HAvERsTlcK V 2,438,635

` TURBINE SYSTEM UTILIZ-ING HOT DRIVING GASES Filed Sept. 3, 1943 2 Sheets-Sheet 2 /47 afm/Ki Patented Mar. 3.0, 1948 TURBINE SYSTEM UTILIZING HOT DRIVING GASES John s. naversuek, Trenton, N. J., assigns: to ne Laval Steam Turbine Company, Trenton, N. J a corporation of New Jersey Application September 3, 1943, Serial No. 501,101

This invention relates to turbine systems and particularly to systems utilizing hot driving gases.

-In the usual arrangement for driving a turbine by means of gases at high temperature, the air is rst compressed, passed through a heat exchanger to receive heat from exhaust gases, and introduced into a combustion chamber in which fuel is burned therein. The products of combustion are then passed through one or more turbines and exhausted through the heat exchanger to pre-heat the compressed air. A serious drawback in any such system is that the products of combustion must pass through the turbine or turbines, wherein they may cause both corrosion and erosion with the result that only high grade fuels may be used, the use of coal, which gives rise to solid products, or the use of low grade fuels, which give rise to highly corrosive products, being thereby precluded.

In accordance with the present invention, systems may be provided in which not only are products of combustion excluded from the turbines, which are operated with highly heated air as the motive fluid, but the entire air exhausted from the turbines will pass to the combustion chamber or chambers to secure the most effective utilization of all of the heat energy available.

The foregoing objects of the invention, as well as other objects relating to details of arrangement and operation, will be apparent from the following description read in conjunction with the accompanying drawings, in which:

Fig. 1 isa diagram showing one system providedA in accordance with the present invention; and

Fig. 2 is similar diagram but showing the addition of heat between turbine stages.

Referring rst to the modification of Fig. 1, there is illustrated therein two combustion chambers 32 and 34 into which fuel is introduced respectively at 36 and 38 to be burned ,in air admitted thereto, as hereinafter described. The combustion chambers may take forms of highly varying nature, depending upon the fuel which is burned. If the fuel is oil or gas, it may be injected in the form of a jet or spray. Ii the fuel is finely powdered coal, it may be similarly injected in dispersed form. On the other hand, the combustion chamber may involve the introduction of coal or other solid fuel in relatively large pieces, in which case a stoker may be used.

The products of combustion frm the chamber 34 pass through an initial portion 40 of the passages in the heat exchanger 42. The products of combustion from 32, on the other hand, mingle with the products of combustion from 3l through Claims. (Cl. 60-59) later portions 44 of the combustion gas passages in the heat exchanger. By reason of counterflow arrangement with the air passage or passages 46 there may be secured more effective heating of the air to a high temperature. The air is compressed by the centrifugal compressors 38 and 50 and. after receiving heat, drives, in series, the turbines 52, 56, and SEL The air exhausted from the last turbine passes through the connections 58 and to the respective combustion chambers.

Fig. 2 shows a modication, in which re-heating of air between stages is eected. In this modification, a single combustion chamber B2 is provided receiving fuel at 6d and air from the last stage turbine. The products of combustion are in this case split, with a major portion owing through the connection BS to the initial gas passages l of the heat exchanger 63. Some of the combustion gases are diverted at l2 to a heat exchanger 1d. passing through the passage or passages 16 thereof and thence through connection 'it to mingle with the combustion gases passing through l@ in the heat exchanger 68, and with them passing through a'further portion of the gas passages indicated at 3G.

Another portion of the combustion gases is diverted at 82 to the passages 84 of the heat exchanger 8i, from which the gases iiow through 88 to mingle with the other combustion gases to pass with them through the latter portions 90 of the heat exchanger passages.

The air is compressed by the two compressor stages 92 and 94 and passes, as indicated at 96, in heat exchange with the gases flowing through the heat exchanger. The heated air passes from 68 to the high pressure turbine 98, whence it flows through the passages |00 in the heat exchanger 14, in which its temperature is raised prior to its entering the intermediate stage turbine |02. From this the air passes for further re-heating ,through the passages |04 in the heat exchanger 86, from which in turn it enters the last stage turbine I 06 arranged to deliver power through the shaft |08. From |06 the exhaust air passes to the combustion chamber.

By reason of the re-heating between the stages in this modification, the efliciency may be increased, inasmuch as the eiilciency of a gas turbine increases rapidly with rise of temperature.

It will be clear that numerous changes may be made in detaik of the invention without departing from the scope thereof as defined in the following claims.

What is claimed is:

1. A turbine system comprising a plurality of aesaeso' turbines arranged in series. means ior cmpressing air driven by at least one of the turbines, means for heating the air. means for directing the heated air to the turbines to drive the same, and means for burning fuel in air exhausted from the turbines, the means for heating the air utilizing the products of said combustion, said means for heating the air involving an air passage. means for subjecting the air in counterow arrangement to heat exchange with one stream of said products of combustion and means for adding to said stream at an intermediate point thereof an additional stream of said priiucts of combustion.

2. A turbine system comprising a plurality of turbines arranged in series, means for compressing air driven by at least one of the turbines, means for heating the air, means for directing the heated air to the turbines to drive the same, means for burning fuel in air exhausted from the turbines, the means for heating the air utilizing the products of said combustion. and means for reheating the air between turbine stages', said means for heating the air involving an air passage. means for subjecting the air in countermeans.

JOHN S. HAVERSTICK.

REFERENCES CITED The following references are of record in the ille of this patent:

FOREIGN PATENTS Number Country Date 520,654 Germany Mar. 17, 1931 215,485

Switzerland Oct. 1,1941 

